Photographic prints of Watson and Crick at the Cavendish laboratory posing with the double helix model shortly after their discovery was announced. All photographs by A.C. Barrington Brown of Cambridge.

Various photographic prints of DNA X-ray images (A and B-form), including the famous "Photograph 51" (B-form), which was taken by Raymond Gosling while working under Rosalind Franklin. The A-form photograph includes handwritten notation by Watson on…